1. Field of the Invention
The present invention relates to a structure for an automotive vehicle bonnet for closing an engine compartment of the vehicle.
2. Description of the Related Art
FIGS. 12A, 12B are side views of conventional automotive vehicle bonnets.
In a common automotive vehicle 100 shown in FIG. 12A, a bonnet 103 attached via hinges 102 to a body 101 side of the vehicle in such a manner as to be opened and/or closed is held open by hooking up a distal end of an opening stay 104 extending from the body 101 side to the vicinity of a distal end of the bonnet 103 (hereinafter, referred to as a xe2x80x9cprior art No. 1xe2x80x9d) By the way, the reduction in weight of the opening stay is also important to reduce the weight of the automotive vehicle 100.
FIG. 12B shows that a bonnet 103 is held open by hooking up a distal end of an opening stay 104 extending from a body side of the vehicle to a hook retaining portion 105 provided in the vicinity of a hinge 102 (herein after referred to as a xe2x80x9cPrior art No. 2xe2x80x9d). Since the opening stay 104 is hooked up to the vicinity of the hinge 102, the length of the opening stay 104 can be reduced.
In FIG. 12B, it is usual to press the distal end of the bonnet 103 downwardly to close the bonnet 103 that is being held open. However, it may happen that the distal end of the bonnet 103 is pressed downwardly with the opening stay 104 being hooked up to the bonnet 103. Since a distance from the hinge 102 which functions as a closing fulcrum to the hook retaining portion 105 is short, a large downward load is applied to the hook retaining portion 105 and its mounting portion. Due to this, sufficient rigidity needs to be secured at the hook retaining portion 105 and the vicinity of its mounting portion.
An automotive vehicle bonnet whose rigidity is improved is known in, for example, JP-A-11-91627 entitled xe2x80x9can automotive vehicle hood structurexe2x80x9d (hereinafter, referred to as a xe2x80x9cprior art No. 3xe2x80x9d).
Disclosed in this prior art No. 3, as shown in FIG. 13A, a bonnet 203 in which a bonnet inner panel 202 is overlaid on and joined to a bonnet outer panel 201.
Furthermore, in the above prior art No. 3, as shown in FIGS. 13A and 13B, a plate-like reinforcement 216 is disposed on a front central portion of the bonnet inner panel 202 at a position where a striker 209 and rubber bumpers 210, 210 are provided, and this reinforcement 216 is joined to the bonnet inner panel 202 with a predetermined space being provided therebetween, whereby a closed section 217 is formed between the two members 202, 216.
As a result of this, according to the prior art No. 3, when the bonnet 203 is pressed downwardly in an attempt to close the same, the bonnet outer panel 201 and the bonnet inner panel 202 can be prevented from being deformed at the position where the striker 209 and the rubber bumpers 210, 210 are provided.
However, it is not possible to apply the contents of the prior art No. 3 directly to the prior art No. 2. The prior art No. 3 is such that it improves the overall rigidity of the portion of the bonnet inner panel 202 where the closed section 217 is provided but does not improve the surface rigidity of the portion where the striker 209 and the rubber bumpers 210, a 210 are provided.
On the other hand, in the prior art No. 2 shown in FIG. 12B, since the hook retaining portion 15 is provided in the vicinity of the hinge 102 on the bonnet 103, an extremely large concentrated load is applied to the hook retaining portion 105 and its mounting portion. A further device needs to be contrived to secure sufficient rigidity at the hook retaining portion 105 and the vicinity of its mounting portion in order to deal with such an excessively large load. It is not a good idea to reinforce the hook retaining portion 105 and the vicinity of its mounting portion with a simple plate member as done in the above prior art No. 3 because the thickness of the plate member increases, whereby the weight thereof increases.
To cope with the above problem, an object of the invention is to provide a technique for enabling not only the improvement in rigidity of a portion to which a distal end of an opening stay is hooked up with a reinforcement member while attempting to reduce the weight of the opening stay but also the reduction in weight of the reinforcement member.
With a view to attaining the above object, according to an aspect of the invention, there is provided an automotive vehicle bonnet structure, comprising: an opening stay extending from a vehicle body side; a hook retaining portion disposed on the vicinity of a hinge between a bonnet and a vehicle body, for hooking up a distal end of the opening stay to hold the bonnet in an ope state; and a reinforcement member incorporated in the bonnet, for reinforcing the hook retaining portion, wherein the reinforcement member is constituted by an extruded member having a closed section, i.e. a hollow extended member.
Since the distal end of the opening stay for holding the bonnet open is hooked up to the hook retaining portion provided in the vicinity of the hinge, the opening stay can be made short, and as a result of this, the opening stay can be made lighter in weight.
Since the reinforcement member is the extruded member having the closed section, although it is thin, the reinforcement member has high bending and torsional rigidities, and moreover, the member is light in weight. Thus, the hook retaining portion can be sufficiently reinforced with the highly rigid reinforcement member.